Chemical heating pad for permanent hair waving



April 11, l939 F. 1 REYNOLDS 2,153,678

CHEMICAL HEATING PAD FOR PERMANENT HAIR WVING.

Filed Nov. 8, 1938 Patented Apr. Il, 1939 v12.1.fais1t UNITED STATESPATENT `ol-"r-'lc'i-z FrederickL. Reynolds, Mill Valley, Calif.,assignor to United States Appliance Corporation,

., a corporation of Cali- San Francisco, Calif i'ornia ApplicationNovember 8, 1938, Serial No. 239,482 s claims. (ci. '13a-sez) Thisinvention relates generally to the construction of chemical heatingpads, particularly pads suitable for carrying out heating operations lin permanent hair. waving. The subject matter 5 disclosed and claimedherein has been continued in part from my co-pendingl application-Serial No. 176,229, led November 24, 193'?.

In said co-pending application Serial No..

176,229, led November 24, 1937, there is disclosed a chemical heatingpad for permanent hair waving, making use of an inner assembly adaptedto be moistened with a chemical solution for carrying out an exothermicreaction. 4The inner assembly is enclosed by a protective wrapper, andincludes absorbent material together with aluminum foil. The chemicalnecess'ary for exothermic reaction with the aluminum foil, is carried bythe chemical solution. y

It is an object of the present invention to provide a chemical'heatingpad of vthe above character which willbe entirely safe for use by beautyparlor operations, particularlywith respect to possible re hazards. v

A further objectof the invention is toprovide a pad of the abovecharacter whichy will be immune to deterioration before use, and whichover a comparatively long period of time will react in substantially thesame manner with a solution of given strength.

Further objects of the invention will appear from the followingdescription in which the preferred embodiments of the invention havebeen set forth in detail in conjunction with the,ac`

companying` drawing.

. Referring to the drawing:4

Fig. lis a perspective view illustrating a pad incorporating the presentinvention and showing the manner'in which chemical solution can be 40applied to the same.

Fig. 2 lis a perspective view illustrating the i manner in which the padcan be folded after application of chemical solution. Figs. 3 and 4 areplan views illustrating how the marginal edges of the outer'f Wrappercan be folded over to form a packet, shown in 'complete form in Fig. 4.n Flg.`5 is a greatly enlarged cross-sectional detail illustrating themanner in which the aluminum' and associated sheets of absorbentasbestos, are perforated. l. l

Fig. 6 is an enlarged cross-sectional detail taken along the line 6--6of Fig. 1, and showing a simple form of attachment to thecuter foilcovering and the stitching which can be used for retaining -the sheetsof vasbestos material assembled with respect to the aluminum foil. Fig.'I is an end elevational view ypartly in cross-section showing the padas applied to a hair curler and held in place by a suitable clamp.Referring to the embodiment of the invention illustrated in the drawing,I have shown a pad consisting of an inner assembly I0, together with anouter covering I I.. 'I'he assembly I0 consists l of a sheet I2 ofaluminum foil, between the two sheets I3 of absorbent material. Thesheets I3 are of non-inflammable mineral ber, preferably absorbentasbestos paper. The thickness of the aluminum foil may be varieddepending f is preferably perforated as illustrated, as by passing itthrough a suitable perforating -appliance. whereby perforations I6 areformed over the entire area of the assembly. Fig. 5 illustrates. 25the'perforations I 6 extending through the assembly, so that in effectthe openings in the individual sheets of asbestos and aluminum foil arein registry. It is preferable to form these 30 perforations by apiercing appliance so that there is no punching out of material, such aswould decrease the effective reactive surface and vmass of aluminumfoil.

The outer wrapper or protective covering Il can consist of a sheet ofaluminum or tin foil Il, provided with an inner liner I8 of suitablematerial such as waxed or parchment paper. Such a liner affords achemically inert membrane to prevent reaction between the chemical solu-40 tion and the foil covering Il. The inner assembly can be enclosedwithin the covering Il in a suitable way, as for example by having theassembly attached by means of elements 2I to the covering.

Inmaking use of the pad described above a suitable chemical solution isprovided, to saturate the asbestos sheets I3. Solutions whichI canemploy contain chemicals such as a salt of a heavy metal, like coppersulphate, capable of solution whichcan be employed with good results. isas follows:-

'Sufficient Water to make 30 cc. of solution.

The ammonium chloride initially activates the reaction and depresses thepH value of the solution. As the reaction of the solution on thealuminum proceeds, and the solution is heated to an elevatedtemperature, some decomposition of the ammonium chloride occurs, withthe result that the pH value of the solution is raised, to temper thereaction and extend the heating period.

Various expedients can be utilized to saturate the asbestos sheetsI3-With the chemical solution. Thus the operator may have a small`measuring device such as a measuring dropper 22, by means of whichdefinite amounts of solution can be applied. Assuming that such adropper or applicator is used, it is lled with a definite amount ofsolution and the solution is supplied to the assembly I0. The solutionimmediately penetrates through the perforations to saturate all parts ofthe assembly.

'I'he pad illustrated is intended for croquinole permanent waving and isof such length that it l can be folded as illustrated in Fig. 2, beforebeing applied over a conventional croquinole curler. The'entire pad canbe folded over as shown in Fig. 2, and the marginal edges of thecovering II which Yextend out beyond the edges of the folded assemblyI0, can be folded over as a safety precaution against leakage ofsolution. As indicated in Fig. 3, after folding over as indicated inFig. 2, marginal edges IIa are folded over followed by a folding over ofthe marginal edges I Ib, as shown in Fig. 4. A complete folded packet asshown in Fig. 4 (designated generally by number III!) can be appliedover a strand of wound hair, as for example in the manner illustrated lin Fig. 7. In this instance a strand of hair is shown wound about thecroquinole curler 23, c arried by the croquinole protector 24. Thefolded packet III) is retained about the wound strand by suitablemeans-such as the spring clip 25.

It isto be understood that in using the chemical pad described above,the Wound hair .is moistened with aqueous waving solution, in the samemanner as now practiced in conventional permanent hair Waving. It isalso `to beunderstood that the dimensions of the pad can be varied tosuit different requirements, as for example to enable application of thepad to a strand of hair wound about an extended rod spiral fashion, asis Well known to those skilled in the art.

Shortly after applying the chemical solution to the inner assembly, theexothermic reaction commences, and by the time-.the folded packet hasbeen applied about the Wound hair, heat is being developed to transferheat to--the wound hair. The temperature of the hair is rapidly elevatedto steaming temperature, and the steaming period is extended overa;suflicient period of time to lend permanency to the wave. During theheating period the aluminum foil is-substantially entirely consumed bythe chemical reaction.l

'Specific reference has been madev to the use of asbestos paper toretain the chemical solution. Also it hasbeen 'pointed .out that thesolution makes use of an active oxidizing agent like sodium chlorate. Atthe end of the Waving opera'.-

solution.

tion at least a part of this oxidizing agent is still present. If thesheets I3 were made of ordinary absorbent paper or like material,impregnation of the cellulose fiber with the oxidizing agent wouldproduce a highly inflammable article, and thus create a re hazard. Suchafire hazard is entirely avoided by the use of an inert non-inflammableber like asbestos, thus making it possible for the operator to discardthe pads after they have been used, without particular care as to themanner of their disposal. In addition should one apply chemical solutionto a pad and then neglect to apply the pad to a curler, the relativelyhigh temperature attained Within the pad can cause n'o charring of theinner assembly, such as would occur should cellulose vfiber likeblotting paperbe employed.- Charring of the innerl assembly can bedangerous since it may result in spontaneous combustion or an ex'-plosion.

The perforations in the asbestos sheets I3 facilitate saturation of thesheets with the chemical Perforating the aluminum sheets I3 augments theedge area of the aluminum foil which is exposed to the chemicalsolution. Carrying out the perforating operation as described tends tocause sheets I3 to adhere to opposite sides of the aluminum foil so thatthe side surfaces of the aluminum foil are retained in physical contactwith the asbestos sheets.

'I'he aluminum foil employed is preferably one having its surfacescovered by a thin oil film. This oil film may be of ordinary petroleumlubricating oil, applied at the time the foil is manufactured, andserves to protect the surfaces of the foil against further oxidation. Itis desirable that this oil lm remain substantially intact because whenthe strength of the solution is made to enable an optimum type ofreaction with the aluminum foil', with commencement of the steamingperiod within a given period of time, such factors should not be subjectto gradual changes. In this connection it should be explained that thenature of the Oil film affects the time period for commencing activereaction of the` solution with the aluminum, and in addition it protectsthe foil against oxidation. 'Materials made of cellulose fiber. as forexample blotting paper, tend to gradually absorb such an oil film, withthe result that the action obtained for a given strength of' solution issubject to changes. However, asbestos paper because of its inherentcharacteristics, has been found not to absorb or modify the oil film toany material degree. Thus the characteristics of the pad restrength fsolution.

I claim:

1. In a chemical heating pad for permanent hair waving, a sheet ofmetallic foil, and a sheet of asbestos paper disposed in intimatecontact withone side of the aluminum foil, the sheet of asbestos fiberbeing adapted to, be saturated with a chemical solution for exothermicreaction with the aluminum foil. f

2. In a chemical heating pad for permanent hair waving, a sheet ofaluminum foil, a sheet of absorbent asbestos paper in contact with oneside of the aluminum foil, said sheet of asbestos paper being capable ofretaining a chemical solution for exothermic reaction with the aluminumfoil, both Wrapper.

. main substantially constant over a long period plurality of sheets ofabsorbent asbestos paper4 3. In a chemical heating pad for permanenthair Waving, a sheet of aluminum foil, and a exible sheet of absorbentasbestos paper in intimate contact with one side of the aluminum foil,both the aluminum foil and the asbestos paper being perforated, thesheet of asbestos paper `being capable of retaining a chemical solutionfor exothermic reaction with the aluminum foil. 4. In a chemical heatingpad for permanent hair waving, a sheet of aluminum foil, and a disposedin intimate contact with the side surfaces of the aluminum foil,perforations extendthe one side of the foil. the foil having a thin 10lm of oil covering the same.

' FREDERICK L. REYNOLDS.

